EUROCORES_EUROQUASAR-1. Call_QuDeGPM_Quantum Degenerate Gases for Precision Measurements

Atom interference has been applied in many pioneering experiments ranging from fundamental studies to precision measurements. The techniques of laser cooling and trapping have allowed the realization of bright sources of macroscopic matter waves. The central goal of the Collaborative Research Project QuDeGPM is to build on this expertise and use interference of quantum degenerate macroscopic matter waves for a new generation of precision measurements. Two sets of applications are envisioned: (1) Precision determination of fundamental constants and inertial forces in free space, and (2) Interferometers for trapped atoms close to the surface as a microscope for highly sensitive measurements of surface forces on m length scale. To achieve the ultimate sensitivity we will engineer the interactions between the atoms and create non-classical matter-wave quantum states to beat the standard quantum measurement limit. Ultracold degenerate quantum gases with their inherent coherence and narrow spread in space and momentum promise to be the ideal starting point for precision matter wave interference experiments, similar to lasers for light optics. In contrast to light, atoms interact with each other, and the physics of degenerate quantum gases is in many cases dominated by these interactions. This can be an advantage, allowing tricks from non-linear optics like squeezing to boost sensitivity, and a disadvantage, resulting in additional dephasing due to uncontrolled collisional phase shifts. We will exploit recent advances in controlling these interactions by Feshbach resonances to pick out the advantages and to suppress the disadvantages caused by the interactions. Much of the planned work will be very fundamental and exploratory as many of the capabilities together with possible limitations have yet to be investigated. The collaborative research project QuDeGPM focuses European efforts on precision measurements with quantum degenerate gases and in particular with Bose-Einstein condensates by strongly interconnecting the individual projects of leading European researchers in the field. The individual projects feature complementary expertise using different physical realizations, thus avoiding inefficient double work. The project is organized along the main objectives of (i) performing precision atom interferometry with quantum degenerate gases, (ii) using quantum degenerate gases for precision surface probing, and (iii) exploring, realizing, and testing novel measurement schemes with non-classical matter wave states.